The present invention relates to drive track supports for track-laying machines. Specifically, the present invention deals with a resilient suspension system for isolating track vibration in a track-laying vehicle, such as a track drive skid steer loader.
A track driven machine has identical track frames on opposite sides of the machine frame. Each track frame mounts an endless track which is driven by a drive sprocket that is driven from a shaft of a drive motor. The track frames are supported relative to a machine frame. Contact with the ground during machine motion creates vibration in the track. Additional track vibration is created by the impact forces caused by the track tread and drive lugs. This track vibration is transmitted to the track frame and to the vehicle or machine frame and the operator's platform. Currently, there exist various track suspension systems to minimize vibrations; U.S. Pat. Nos. 1,474,918 and 5,899,543 are representative of the prior art.
U.S. Pat. No. 1,474,918 discloses a suspension system for a track-laying vehicle having an undercarriage rocking cross-beam with ends attached to each side of the track frame by means of spherical bearings. The cross-beam has two springs of limited flexibility mounted near the two ends for attaching the cross-beam to the machine frame. Additional suspension is provided by a similar spring mounted on top of the roller wheels assembly of each track.
U.S. Pat. No. 5,899,543 teaches a suspension system for a tracked vehicle having a roller wheel assembly comprising six roller wheels rotatably attached to a roller wheel beam having three wheels on each side of the beam. The beam has two ends with a T-shaped mounting bracket rigidly attached to each end, wherein the leg of the T-shaped bracket has a resilient component attached to each side of the leg. The T-shaped bracket is to be fitted into a corresponding female U-shaped mounting bracket that is rigidly attached to an undercarriage support beam that is ultimately attached to the machine frame. The U-shaped mounting bracket also has resilient component on each inner side of the “U” while having space in between to receive the T-shaped bracket. This design is an attempt to dampen vibration coming from the roller wheels by using resilient components as contact points.
The need still exists for a simple resilient track suspension system that will provide effective suspension and effective overall track vibration isolation.